A Florida State University and University of Alaska Fairbanks research team has uncovered a new species of duck-billed dinosaur, called Ugrunaaluk Kuukpikensis (meaning “ancient grazer of the Colville River”), a 30-footlong herbivore that endured many a cold Arctic night and, likely, even snow.
“The finding of dinosaurs this far north challenges everything we thought about a dinosaur’s physiology,” said FSU Professor of Biological Science Greg Erickson. “It creates this natural question. How did they survive up here?”
Discovered at the Prince Creek Formation in Alaska, a unit of rock that was deposited on an arctic, coastal flood plain about 69 million years ago, the Ugrunaaluk Kuukpikensis is now believed to be the northernmost dinosaur species to have ever lived.
Even though, at the time, the world was hotter than it is right now, these giant herbivores still had to endure long stretches of winter darkness, and live in place where the average temperature barely exceeded 6 degrees Celsius.
“What we’re finding is basically this lost world of dinosaurs with many new forms completely new to science,” Erickson said.
The majority (around several thousand) of the bones of the Ugrunaaluk Kuukpikensis were collected from a single layer of rock called the Liscomb Bonebed. Most of them come from juvenile dinosaurs, roughly 9 feet-long and 3 feet-tall at the hip, believed to have been killed during a sudden attack.
Having analysed the new species’ bone structure, these dinosaurs were found to be most closely related to Edmontosaurus, another type of duck-billed prehistoric giant that lived roughly 70 million years ago in Alberta, Montana and South Dakota, USA.
However, the combination of features, observed in the Ugrunaaluk Kuukpikensis, is very different from those seen in Edmontosaurus, showing very unique skeletal structures in the area of the skull, and especially around the mouth.
“Because many of the bones from our Alaskan species were from younger individuals, a challenge of this study was figuring out if the differences with other hadrosaurs was just because they were young, or if they were really a different species,” said study co-author Patrick Druckenmiller. “Fortunately, we also had bones from older animals that helped us realize Ugrunaaluk was a totally new animal.”
Despite the extremely difficult weather conditions present on the dig site, Erickson and Druckenmiller will continue to mine Prince Creek Formation for additional skeletons, and delve deeper into how these remarkable animals lived under conditions thought to be too harsh for reptilian dinosaurs.
According to Erickson, Alaska is the final frontier – virtually unexplored in terms of vertebrate palaeontology. “So, we think we’re going to find a lot of new species.”
The paper was published in the journal Acta Palaeontologica Polonica.